Critical current in planar SNS Josephson junctions

Specific features of the proximity effect and Josephson behavior of submicron planar SNS junctions fabricated by electron beam lithography and shadow evaporation have been studied experimentally and theoretically. The critical current of the junctions has been found to drastically increase with a decrease in temperature, which is associated with a change in the effective size of the weak link owing to the additional SN interface.     

A Novel Synthetic Approach to Phosphorylated Peptidomimetics

It has been shown that the derivatives of diethyl 5‐amino‐2‐phthalimidoalkyl‐1,3‐oxazol‐4‐ylphosphonates can be employed in the synthesis of phosphorylated peptidomimetics containing the phosphonoglycine residue. The reaction of diethyl 5‐alkylamino‐2‐aminoalkyl‐1,3‐oxazol‐4‐ylphosphonates with unsaturated azlactones was utilized to obtain phosphorylated peptidomimetics with dehydroamino acid moieties. The double bond in the latter was reduced with zinc in acetic acid to provide the corresponding saturated peptidomimetics containing a diethoxyphosphoryl group in the side chain.     

Development of a convenient synthetic route to aminochromenes via Buchwald C-N coupling

A convenient new synthetic route to p-aminophenylaminobenzo- and naphthopyrans was developed via palladium-catalyzed C-N coupling. It was demonstrated that novel targeted aminoderivatives reveal photochromic properties. The structure of intermediate p-nitrophenylaminochromenes was confirmed by X-ray crystallographic analysis.     

Superconducting decay length in a ferromagnetic metal

The complex decay length ξ characterizing the penetration of superconducting correlations into a ferromagnet due to the proximity effect is studied theoretically in the framework of the linearized Eilenberger equations. The real part ξ₁ and imaginary part ξ₂ of the decay length are calculated as functions of exchange energy and the rates of ordinary, spin-flip, and spin-orbit electronic scattering in a ferromagnet. The lengths ξ_1,2 determine the spatial scales of, respectively, the decay and oscillation of a critical current in SFS Josephson junctions in the limit of a large distance between superconducting electrodes. The developed theory provides the criteria of applicability of the expressions for ξ₁ and ξ₂ in the dirty and clean limits, which are commonly used in the analysis of SF hybrid structures. The text was submitted by the authors in English.     

Morphometric model of lymphocyte as applied to scanning flow cytometry

The peripheral blood lymphocytes of normal individuals are investigated by methods of specialized light microscopy. Lymphocytes as a whole and T-cell subpopulation are considered. Lymphocyte structure is characterized with reference to polarizing scanning flow cytometry. The lymphocyte and lymphocyte nucleus shapes are analyzed. Linear correlation dependence between sizes of lymphocyte and its nucleus is indicated. A morphometric model of a lymphocyte is constructed using the obtained data. The findings can be used, for instance, as input parameters to solve the direct and inverse light-scattering problems of turbidimetry, nephelometry, and flow cytometry.     

Higher-Order Solitons in the N-Wave System

The soliton dressing matrices for the higher-order zeros of the Riemann–Hilbert problem for the N -wave system are considered. For the elementary higher-order zero, that is, whose algebraic multiplicity is arbitrary but the geometric multiplicity is 1, the general soliton dressing matrix is derived. The theory is applied to the study of higher-order soliton solutions in the three-wave interaction model. The simplest higher-order soliton solution is presented. In the generic case, this solution describes the breakup of a higher-order pumping wave into two higher-order elementary waves, and the reverse process. In non-generic cases, this solution could describe (i) the merger of a pumping sech wave and an elementary sech wave into two elementary waves (one sech and the other one higher order); (ii) the breakup of a higher-order pumping wave into two elementary sech waves and one pumping sech wave; and the reverse processes. This solution could also reproduce fundamental soliton solutions as a special case.     

Resonant Josephson tunneling through S-I-S junctions of arbitrary size

The Josephson tunneling current in S-I-S structures where the main current transport channel is resonant tunneling through an isolated localized state is calculated using the Bogolyubov-de Gennes equations. It is shown that the efficiency of equilibrium Josephson resonant tunneling is determined only by the ratio of the width of the resonance level to the absolute value of the order parameter for the superconducting electrodes with arbitrary relationships among the system parameters. Zh. éksp. Teor. Fiz. 112, 342–352 (July 1997)